Connecting Actuators in Parallel Safely: Ensuring Optimal Performance and Longevity

When working on circuit designs involving parallel connections of actuators, it is crucial to ensure that each actuator operates within its specified current rating. This article aims to provide a comprehensive guide on the best practices for connecting actuators in parallel, ensuring both the longevity and reliability of your circuit. We will discuss key considerations such as current rating, heat dissipation, and the importance of testing.

Understanding the Basic Configuration

Let us consider a scenario where you have two actuators connected in parallel, with each actuator rated to take 3A. If your power supply can supply up to 6.3A, you might wonder whether it is safe to provide 3.33A to each actuator and if an additional 0.33A (11% over the rated current) could potentially damage the actuators. The answer depends on various factors including tolerance levels, heat dissipation, and current regulation.

Key Considerations for Parallel Actuator Connections

Tolerance Levels

Firstly, it is essential to check the specifications of the actuators for any tolerance levels. Some devices can handle slight overcurrent conditions, but a current of 3.33A, which is 11% over the rated current, might be too much and could lead to failure. This is especially critical as prolonged exposure to such conditions can considerably reduce the lifespan of the actuators.

Heat Dissipation

Another crucial aspect is heat dissipation. Overcurrent can significantly increase heat generation. If the actuators are not designed to handle this additional heat, it could result in thermal failure. Therefore, it is important to ensure that the power supply and the circuit can handle the additional heat generated by the increased current. Regular monitoring of the actuators' temperature is recommended during testing phases to ensure they remain within safe operating conditions.

Current Regulation

It is also important to ensure that there is a current-limiting device or circuit in place to prevent overcurrent conditions. This is especially essential if you are consistently supplying a higher current than the actuators' rated levels. A current-limiting device can help protect the actuators and prevent damage due to continuous overcurrent.

Testing and Validation

Conducting thorough testing of the actuators under the higher current for a short period while monitoring their temperature is a critical step. This can help you determine if the actuators can handle the excess current without any damage. Proper testing can provide valuable insights into the performance and safety of your circuit design.

Power Supply Configuration

In the aforementioned scenario, with two actuators in parallel drawing 3 amps each, totaling 6 amps, your power supply can supply up to 6.3 amps. This configuration ensures that there is a small reserve of 0.3 amps. Therefore, your power supply can handle the current requirements of the actuators without overloading.

Controller Input and Inrush Current

Regulating the current flow to each actuator is achieved through the control input, which is managed by a controller microcontroller. The actuators will consume only the current they need, and if they are rated to draw 3A from the power supply at the nominal voltage, they will take only 3A. However, it is important to be mindful of inrush current, which can occur during the initial operation of the actuators. Inrush current can be higher than the steady-state operating current and must be accounted for in the design.

Conclusion

Ensuring that actuators in parallel connections operate within their specified current ratings is paramount to protect their longevity and performance. By carefully considering tolerance levels, heat dissipation, current regulation, and conducting thorough testing, you can design a robust and efficient circuit. If you consistently need to supply a higher current, it is advisable to either adjust your power supply or choose actuators with a higher current rating. Proper design and testing can help safeguard your actuators and ensure the success of your project.